A couple of months ago, I posted about ways that I waterproof my backpack. As of that post, I had given my backpack a few tests with my recently rubberized pack, using Rust-Oleum Leak Seal Flexible Rubber Sealant. The rubber had a few winter trips, and a few spring trips under its belt, and, it worked perfectly, the bottom of my pack was always dry – so the rubber did its job!

However, after the workout I had given it, as you can see from the photo below, there are a few places where it is starting to come off, mostly around the seam on the edges. I can also now pinch a section, and peel off a chunk. Now that the rubber has sufficiently dried, it is definitely cracking off the fabric a bit more.

There are a few methods to fixing this, using the same stuff…

Patch repair the places where it is coming off

Get the old rubber off, and then spray on a new coating of the rubber

Find some way to get better adhesion to the nylon of the backpack

I do not have any super-wet trips planned in the future as of yet (and it’s spring – I do not have to worry about bedding down in 0 degree weather in the snow anytime soon in a super-soaked sleeping bag), so I am not as concerned with the short term, and there is always the Large Brown Garbage Bag liner for the inside of the pack, along with my other waterproofing methods, so for my next trip or two I am OK.

Being an engineer, it is time to sit down and re-think this, and see if I can come up with a better adhesion solution to get the rubber to stick better onto the nylon…